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                <ol class="chapter"><li class="chapter-item affix "><a href="../../index.html">Andrew's Blog</a></li><li class="chapter-item "><a href="../../posts/linux/linux.html"><strong aria-hidden="true">1.</strong> Linux</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/linux/install_linux.html"><strong aria-hidden="true">1.1.</strong> install linux</a></li><li class="chapter-item "><a href="../../posts/linux/bash_profile.html"><strong aria-hidden="true">1.2.</strong> bash profile</a></li><li class="chapter-item "><a href="../../posts/linux/command_list.html"><strong aria-hidden="true">1.3.</strong> command list</a></li><li class="chapter-item "><a href="../../posts/linux/git_guide.html"><strong aria-hidden="true">1.4.</strong> git guide</a></li><li class="chapter-item "><a href="../../posts/linux/tar.html"><strong aria-hidden="true">1.5.</strong> tar</a></li><li class="chapter-item "><a href="../../posts/Linux/git_cheatsheet.html"><strong aria-hidden="true">1.6.</strong> Git Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/Linux/bash_cheatsheet.html"><strong aria-hidden="true">1.7.</strong> Bash Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/macos/mac.html"><strong aria-hidden="true">2.</strong> MacOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/macos/macos_profiles.html"><strong aria-hidden="true">2.1.</strong> macos profiles</a></li><li class="chapter-item "><a href="../../posts/macos/macos_pwn_env_setup.html"><strong aria-hidden="true">2.2.</strong> macos pwn env setup</a></li></ol></li><li class="chapter-item "><a href="../../posts/swift/swift.html"><strong aria-hidden="true">3.</strong> Swift</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/swift/learn_swift.html"><strong aria-hidden="true">3.1.</strong> learn swift basics</a></li><li class="chapter-item "><a href="../../posts/swift/swift_extensions.html"><strong aria-hidden="true">3.2.</strong> Swift extensions</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_extension.html"><strong aria-hidden="true">3.3.</strong> SwiftUI extensions</a></li><li class="chapter-item "><a href="../../posts/swift/install_swift.html"><strong aria-hidden="true">3.4.</strong> install swift</a></li><li class="chapter-item "><a href="../../posts/swift/task_planner.html"><strong aria-hidden="true">3.5.</strong> implment task panner app with SwiftUI</a></li><li class="chapter-item "><a href="../../posts/swift/swift_cheat_sheet.html"><strong aria-hidden="true">3.6.</strong> Swift Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/swift/yinci_url.html"><strong aria-hidden="true">3.7.</strong> Personal privacy protocol</a></li><li class="chapter-item "><a href="../../posts/swift/swift_regular_exressions.html"><strong aria-hidden="true">3.8.</strong> Swift regular exressions</a></li><li class="chapter-item "><a href="../../posts/ios/how_to_create_beautiful_ios_charts_in_swift.html"><strong aria-hidden="true">3.9.</strong> How to Create Beautiful iOS Charts in Swift</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_source_code.html"><strong aria-hidden="true">3.10.</strong> SwiftUI source code</a></li><li class="chapter-item "><a href="../../posts/swift/use_swift_fetch_iciba_api.html"><strong aria-hidden="true">3.11.</strong> use swift fetch iciba API</a></li></ol></li><li class="chapter-item "><a href="../../posts/ios/ios.html"><strong aria-hidden="true">4.</strong> iOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ios/cocaposd_setup_and_install_for_ios_project.html"><strong aria-hidden="true">4.1.</strong> cocaposd setup and install for ios project</a></li><li class="chapter-item "><a href="../../posts/ios/swiftui_show_gif_image.html"><strong aria-hidden="true">4.2.</strong> SwiftUI show gif image</a></li><li class="chapter-item "><a href="../../posts/ios/implement_task_planner_app.html"><strong aria-hidden="true">4.3.</strong> implement Task planner App</a></li></ol></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c.html"><strong aria-hidden="true">5.</strong> Objective-C</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/objective_c/objective_c_cheat_sheet.html"><strong aria-hidden="true">5.1.</strong> Objective-C Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c_for_absolute_beginners_read_note.html"><strong aria-hidden="true">5.2.</strong> Objective-C Note</a></li></ol></li><li class="chapter-item "><a href="../../posts/dart/dart.html"><strong aria-hidden="true">6.</strong> Dart</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/dart/flutter.html"><strong aria-hidden="true">6.1.</strong> Flutter Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/dart/dart_cheat_sheet.html"><strong aria-hidden="true">6.2.</strong> Dart Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/flutter/flutter_dev_test.html"><strong aria-hidden="true">6.3.</strong> Flutter dev test</a></li></ol></li><li class="chapter-item "><a href="../../posts/rust/rust.html"><strong aria-hidden="true">7.</strong> Rust</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/rust/offline_use_rust.html"><strong aria-hidden="true">7.1.</strong> Offline use rust</a></li><li class="chapter-item "><a href="../../posts/rust/rust_grammer.html"><strong aria-hidden="true">7.2.</strong> rust grammar</a></li><li class="chapter-item "><a href="../../posts/rust/pase_string_and_decimal_conversion.html"><strong aria-hidden="true">7.3.</strong> pase string and decimal conversion</a></li><li class="chapter-item "><a href="../../posts/rust/parse_types.html"><strong aria-hidden="true">7.4.</strong> rust types</a></li><li class="chapter-item "><a href="../../posts/rust/rust_life_cycle.html"><strong aria-hidden="true">7.5.</strong> Rust life cycle</a></li><li class="chapter-item "><a href="../../posts/rust/rust_generic.html"><strong aria-hidden="true">7.6.</strong> rust generics</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implment_matrix.html"><strong aria-hidden="true">7.7.</strong> Rust implement matrix</a></li><li class="chapter-item "><a href="../../posts/rust/rust_sort.html"><strong aria-hidden="true">7.8.</strong> Rust implement sort algorithms</a></li><li class="chapter-item "><a href="../../posts/rust/implement_aes_encryption.html"><strong aria-hidden="true">7.9.</strong> Rust implement AEC encryption and decryption</a></li><li class="chapter-item "><a href="../../posts/rust/implement_trie_data_structure.html"><strong aria-hidden="true">7.10.</strong> implement trie data structure</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_tree.html"><strong aria-hidden="true">7.11.</strong> implement tree data_structure</a></li><li class="chapter-item "><a href="../../posts/rust/list_dir.html"><strong aria-hidden="true">7.12.</strong> list dir</a></li><li class="chapter-item "><a href="../../posts/rust/fast_way_to_implment_object_trait.html"><strong aria-hidden="true">7.13.</strong> fast way to implment object trait</a></li><li class="chapter-item "><a href="../../posts/rust/compress_rust_binary_size.html"><strong aria-hidden="true">7.14.</strong> compress rust binary size</a></li><li class="chapter-item "><a href="../../posts/rust/implment_file_upload_backend.html"><strong aria-hidden="true">7.15.</strong> impliment file upload</a></li><li class="chapter-item "><a href="../../posts/rust/this_is_add_post_cli_implementation_in_rust.html"><strong aria-hidden="true">7.16.</strong> this is add_post cli implementation in rust</a></li><li class="chapter-item "><a href="../../posts/rust/use_rust_implment_a_copyclipbord_cli.html"><strong aria-hidden="true">7.17.</strong> Use rust implment a copyclipbord CLI</a></li><li class="chapter-item "><a href="../../posts/rust/sqlite_database_add_delete_update_show_in_rust.html"><strong aria-hidden="true">7.18.</strong> sqlite database add delete update show in rust</a></li><li class="chapter-item "><a href="../../posts/rust/implementing_tokio_joinhandle_for_wasm.html"><strong aria-hidden="true">7.19.</strong> Implementing tokio JoinHandle for wasm</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_a_crate_for_encode_and_decode_brainfuck_and_ook.html"><strong aria-hidden="true">7.20.</strong> rust implement a crate for encode and decode brainfuck and ook</a></li><li class="chapter-item "><a href="../../posts/rust/slint_builtin_elements.html"><strong aria-hidden="true">7.21.</strong> Slint Builtin Elements</a></li><li class="chapter-item "><a href="../../posts/rust/corporate_network_install_rust_on_windows.html"><strong aria-hidden="true">7.22.</strong> Corporate network install Rust on windows</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_file_how_to_judge_static_link_or_dynamic_link_in_macos.html"><strong aria-hidden="true">7.23.</strong> rust binary file how to judge static link or dynamic link in Macos</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_include_dir_and_get_contents.html"><strong aria-hidden="true">7.24.</strong> rust binary include dir and get contents</a></li><li class="chapter-item "><a href="../../posts/rust/how_to_create_yolov8_based_object_detection_web_service_using_python,_julia,_node.js,_javascript,_go_and_rust.html"><strong aria-hidden="true">7.25.</strong> How to create YOLOv8-based object detection web service using Python, Julia, Node.js, JavaScript, Go and Rust</a></li><li class="chapter-item "><a href="../../posts/rust/implment_builder_proc_macro_for_command_struct.html"><strong aria-hidden="true">7.26.</strong> implment Builder proc-macro for Command struct</a></li></ol></li><li class="chapter-item "><a href="../../posts/java/java.html"><strong aria-hidden="true">8.</strong> Java</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/java/java_grammar.html"><strong aria-hidden="true">8.1.</strong> java grammar and codewar</a></li><li class="chapter-item "><a href="../../posts/java/run_jar.html"><strong aria-hidden="true">8.2.</strong> java run .jar</a></li><li class="chapter-item "><a href="../../posts/java/java_pomxml_add_defaultgoal_to_build.html"><strong aria-hidden="true">8.3.</strong> Java pomxml add defaultGoal to build</a></li><li class="chapter-item "><a href="../../posts/java/java_set_mvn_mirror.html"><strong aria-hidden="true">8.4.</strong> Java set mvn mirror</a></li></ol></li><li class="chapter-item "><a href="../../posts/python/python.html"><strong aria-hidden="true">9.</strong> Python</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/python/convert_pesn.html"><strong aria-hidden="true">9.1.</strong> convert pesn</a></li><li class="chapter-item "><a href="../../posts/python/find_remove_dir.html"><strong aria-hidden="true">9.2.</strong> find and remove dir</a></li><li class="chapter-item "><a href="../../posts/python/timing_message.html"><strong aria-hidden="true">9.3.</strong> wechat send message</a></li><li class="chapter-item "><a href="../../posts/python/use_python_openpyxl_package_read_and_edit_excel_files.html"><strong aria-hidden="true">9.4.</strong> Use python openpyxl package read and edit excel files</a></li><li class="chapter-item "><a href="../../posts/python/sanctum_model_yaml.html"><strong aria-hidden="true">9.5.</strong> sanctum model yaml</a></li><li class="chapter-item "><a href="../../posts/python/how_to_detect_objects_on_images_using_the_yolov8_neural_network.html"><strong aria-hidden="true">9.6.</strong> How to detect objects on images using the YOLOv8 neural network</a></li><li class="chapter-item "><a href="../../posts/python/use_huggingface_model.html"><strong aria-hidden="true">9.7.</strong> use huggingface model</a></li></ol></li><li class="chapter-item "><a href="../../posts/go/go.html"><strong aria-hidden="true">10.</strong> Go</a></li><li class="chapter-item "><a href="../../posts/javascript/js.html"><strong aria-hidden="true">11.</strong> Javascript</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/javascript/js_tutorial.html"><strong aria-hidden="true">11.1.</strong> js tutorial</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_map.html"><strong aria-hidden="true">11.2.</strong> ja map</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_math.html"><strong aria-hidden="true">11.3.</strong> js math</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_object.html"><strong aria-hidden="true">11.4.</strong> js object</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_set.html"><strong aria-hidden="true">11.5.</strong> js set</a></li><li class="chapter-item "><a href="../../posts/javascript/single_thread_and_asynchronous.html"><strong aria-hidden="true">11.6.</strong> single thread and asynchronous</a></li><li class="chapter-item "><a href="../../posts/javascript/this.html"><strong aria-hidden="true">11.7.</strong> js this</a></li><li class="chapter-item "><a href="../../posts/javascript/js_implment_aes.html"><strong aria-hidden="true">11.8.</strong> js implment aes</a></li><li class="chapter-item "><a href="../../posts/javascript/getting_started_with_ajax.html"><strong aria-hidden="true">11.9.</strong> getting started with ajax</a></li><li class="chapter-item "><a href="../../posts/javascript/BinarySearchTree.html"><strong aria-hidden="true">11.10.</strong> binary search tree</a></li><li class="chapter-item "><a href="../../posts/javascript/goole_zx.html"><strong aria-hidden="true">11.11.</strong> goole zx</a></li><li class="chapter-item "><a href="../../posts/javascript/es6.html"><strong aria-hidden="true">11.12.</strong> es6</a></li></ol></li><li class="chapter-item "><a href="../../posts/ruby/ruby.html"><strong aria-hidden="true">12.</strong> Ruby</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ruby/rails_setup_env.html"><strong aria-hidden="true">12.1.</strong> ruby on rails setup environment</a></li><li class="chapter-item "><a href="../../posts/ruby/learn_ruby.html"><strong aria-hidden="true">12.2.</strong> learn ruby</a></li><li class="chapter-item "><a href="../../posts/ruby/ruby_note.html"><strong aria-hidden="true">12.3.</strong> Ruby Note</a></li><li class="chapter-item "><a href="../../posts/ruby/setup_ruby_for_ctf.html"><strong aria-hidden="true">12.4.</strong> Setup ruby for CTF</a></li></ol></li><li class="chapter-item "><a href="../../posts/react/react.html"><strong aria-hidden="true">13.</strong> React</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/react/react_life_cycle.html"><strong aria-hidden="true">13.1.</strong> react life cycle</a></li><li class="chapter-item "><a href="../../posts/react/react_router.html"><strong aria-hidden="true">13.2.</strong> react router</a></li><li class="chapter-item "><a href="../../posts/react/react_this.html"><strong aria-hidden="true">13.3.</strong> react this</a></li><li class="chapter-item "><a href="../../posts/react/react_interviw.html"><strong aria-hidden="true">13.4.</strong> react interview</a></li><li class="chapter-item "><a href="../../posts/react/important_react_interview.html"><strong aria-hidden="true">13.5.</strong> important react interview</a></li><li class="chapter-item "><a href="../../posts/react/react_quick_reference.html"><strong aria-hidden="true">13.6.</strong> react quick reference</a></li><li class="chapter-item "><a href="../../posts/react/redux_quick_reference.html"><strong aria-hidden="true">13.7.</strong> redux quick reference</a></li></ol></li><li class="chapter-item "><a href="../../posts/vue/vue.html"><strong aria-hidden="true">14.</strong> Vue</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/vue/vue_ajax.html"><strong aria-hidden="true">14.1.</strong> vue ajax</a></li></ol></li><li class="chapter-item "><a href="../../posts/angular/angular.html"><strong aria-hidden="true">15.</strong> Angular</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/angular/controller_communication.html"><strong aria-hidden="true">15.1.</strong> controller communication</a></li><li class="chapter-item "><a href="../../posts/angular/creating_custom_directives.html"><strong aria-hidden="true">15.2.</strong> creating custom directives</a></li><li class="chapter-item "><a href="../../posts/angular/directive_notes.html"><strong aria-hidden="true">15.3.</strong> directive notes</a></li><li class="chapter-item "><a href="../../posts/angular/directive_communication.html"><strong aria-hidden="true">15.4.</strong> directive communication</a></li><li class="chapter-item "><a href="../../posts/angular/post_params.html"><strong aria-hidden="true">15.5.</strong> post params</a></li><li class="chapter-item "><a href="../../posts/angular/read_json_angular.html"><strong aria-hidden="true">15.6.</strong> read json angular</a></li><li class="chapter-item "><a href="../../posts/angular/same_route_reload.html"><strong aria-hidden="true">15.7.</strong> same route reload</a></li></ol></li><li class="chapter-item "><a href="../../posts/css/css.html"><strong aria-hidden="true">16.</strong> Css</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/css/use_css_media.html"><strong aria-hidden="true">16.1.</strong> use css media</a></li></ol></li><li class="chapter-item "><a href="../../posts/php/php.html"><strong aria-hidden="true">17.</strong> Php</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/php/for_php_string_implment_some_extemtion_functions.html"><strong aria-hidden="true">17.1.</strong> for php string implment some extemtion functions</a></li><li class="chapter-item "><a href="../../posts/php/php_cheatsheet.html"><strong aria-hidden="true">17.2.</strong> PHP cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.</strong> Windows</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.1.</strong> Windows</a></li><li class="chapter-item "><a href="../../posts/windows/windows10_use_powershell_dedup_redundent_path.html"><strong aria-hidden="true">18.2.</strong> Windows10 use PowerShell dedup redundent PATH</a></li></ol></li><li class="chapter-item expanded "><a href="../../posts/leetcode/leetcode.html"><strong aria-hidden="true">19.</strong> Leetcode</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../../posts/leetcode/rust_leetcode.html" class="active"><strong aria-hidden="true">19.1.</strong> rust leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_codewar.html"><strong aria-hidden="true">19.2.</strong> rust codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/swift_codewar.html"><strong aria-hidden="true">19.3.</strong> swift codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/js_leetcode.html"><strong aria-hidden="true">19.4.</strong> js leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/java_leetcode.html"><strong aria-hidden="true">19.5.</strong> java leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_huawei.html"><strong aria-hidden="true">19.6.</strong> huawei test</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_utils.html"><strong aria-hidden="true">19.7.</strong> rust common functions</a></li><li class="chapter-item "><a href="../../posts/leetcode/olympiad_training.html"><strong aria-hidden="true">19.8.</strong> Computer olympiad training</a></li></ol></li><li class="chapter-item "><a href="../../posts/ctf/CTF.html"><strong aria-hidden="true">20.</strong> CTF</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ctf/CTF_Note.html"><strong aria-hidden="true">20.1.</strong> CTF Note</a></li><li class="chapter-item "><a href="../../posts/ctf/0.1_Web.html"><strong aria-hidden="true">20.2.</strong> Web</a></li><li class="chapter-item "><a href="../../posts/ctf/4.1_Misc.html"><strong aria-hidden="true">20.3.</strong> Misc</a></li><li class="chapter-item "><a href="../../posts/ctf/3.2_PWN_note.html"><strong aria-hidden="true">20.4.</strong> PWN</a></li><li class="chapter-item "><a href="../../posts/ctf/3.1_Crypto.html"><strong aria-hidden="true">20.5.</strong> Crypto</a></li><li class="chapter-item "><a href="../../posts/ctf/3.4_RSA_note.html"><strong aria-hidden="true">20.6.</strong> Rsa attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.5_Base64.html"><strong aria-hidden="true">20.7.</strong> Base64</a></li><li class="chapter-item "><a href="../../posts/ctf/0.0_SQL Injection Cheatsheet.html"><strong aria-hidden="true">20.8.</strong> SQL Injection Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/1.1_SQL_injection.html"><strong aria-hidden="true">20.9.</strong> SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.2_SQL_injection_UNION_attacks.html"><strong aria-hidden="true">20.10.</strong> SQL Injection UNION attacks</a></li><li class="chapter-item "><a href="../../posts/ctf/1.3_Blind SQL injection.html"><strong aria-hidden="true">20.11.</strong> Blind SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.4_Code Injection.html"><strong aria-hidden="true">20.12.</strong> Code Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.5_SSRF.html"><strong aria-hidden="true">20.13.</strong> SSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.6_OS command injection.html"><strong aria-hidden="true">20.14.</strong> OS command injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.7_Local file inclusion.html"><strong aria-hidden="true">20.15.</strong> Local file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.8_Remote file inclusion.html"><strong aria-hidden="true">20.16.</strong> Remote file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.9_CSRFm.html"><strong aria-hidden="true">20.17.</strong> CSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.10_NoSQL injection.html"><strong aria-hidden="true">20.18.</strong> NoSQL injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.11_JSON injection.html"><strong aria-hidden="true">20.19.</strong> JSON injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.12_CTF_Web_SQL_Note.html"><strong aria-hidden="true">20.20.</strong> CTF Web SQL Note</a></li><li class="chapter-item "><a href="../../posts/ctf/2.1_XXE.html"><strong aria-hidden="true">20.21.</strong> XXE</a></li><li class="chapter-item "><a href="../../posts/ctf/2.2_XSS.html"><strong aria-hidden="true">20.22.</strong> XSS</a></li><li class="chapter-item "><a href="../../posts/ctf/2.3_Upload File.html"><strong aria-hidden="true">20.23.</strong> Upload File</a></li><li class="chapter-item "><a href="../../posts/ctf/2.4_serialize_unserialize.html"><strong aria-hidden="true">20.24.</strong> serialize unserialize</a></li><li class="chapter-item "><a href="../../posts/ctf/2.5_Race condition.html"><strong aria-hidden="true">20.25.</strong> Race condition</a></li><li class="chapter-item "><a href="../../posts/ctf/zip_plain_text_attack.html"><strong aria-hidden="true">20.26.</strong> Zip plain text attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.3_pwn HCTF2016 brop.html"><strong aria-hidden="true">20.27.</strong> pwn HCTF2016 brop</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_patch_defense_skill.html"><strong aria-hidden="true">20.28.</strong> PWN Patch defense skill</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_stack_overflow.html"><strong aria-hidden="true">20.29.</strong> PWN stack overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_heap_overflow.html"><strong aria-hidden="true">20.30.</strong> PWN heap overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_format_string_vulnerability.html"><strong aria-hidden="true">20.31.</strong> PWN Format String Vulnerability</a></li><li class="chapter-item "><a href="../../posts/ctf/kali_linux_tutorials.html"><strong aria-hidden="true">20.32.</strong> Kali linux tutorials</a></li><li class="chapter-item "><a href="../../posts/ctf/google_dorks_2023_lists.html"><strong aria-hidden="true">20.33.</strong> Google Dorks 2023 Lists</a></li><li class="chapter-item "><a href="../../posts/ctf/dvwa_writeup.html"><strong aria-hidden="true">20.34.</strong> DVWA WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/bwapp_writeup.html"><strong aria-hidden="true">20.35.</strong> bWAPP WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/sqlilabs_writeup.html"><strong aria-hidden="true">20.36.</strong> sqlilabs WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/pwnable_kr_challenge.html"><strong aria-hidden="true">20.37.</strong> Solutions for pwnable.kr</a></li><li class="chapter-item "><a href="../../posts/ctf/the_periodic_table.html"><strong aria-hidden="true">20.38.</strong> The Periodic Table</a></li><li class="chapter-item "><a href="../../posts/ctf/pwntools_cheatsheet.html"><strong aria-hidden="true">20.39.</strong> Pwntools Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/gdb_cheatsheet.html"><strong aria-hidden="true">20.40.</strong> GDB Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/iltes/iltes.html"><strong aria-hidden="true">21.</strong> ILTES</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/iltes/iltes_writing.html"><strong aria-hidden="true">21.1.</strong> ILTES Writing</a></li></ol></li></ol>
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                        <h1 id="leetcode-rust-implementation"><a class="header" href="#leetcode-rust-implementation">Leetcode rust implementation</a></h1>
<h2 id="add-two-numbers"><a class="header" href="#add-two-numbers">add-two-numbers</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>use crate::list::ListNode;

/// @number 2
/// @title Add Two Numbers
/// @url https://leetcode.com/problems/add-two-numbers
/// @difficulty medium

struct Solution;

impl Solution {
    pub fn add_two_numbers(l1: Option&lt;Box&lt;ListNode&gt;&gt;, l2: Option&lt;Box&lt;ListNode&gt;&gt;) -&gt; Option&lt;Box&lt;ListNode&gt;&gt; {
        let mut head = None;
        let mut cursor = &amp;mut head;
        let mut one = &amp;l1;
        let mut two = &amp;l2;

        let mut step_in = false;
        while one.is_some() || two.is_some() {
            let one_value = if one.is_some() { one.as_ref().unwrap().val } else { 0 };
            let two_value = if two.is_some() { two.as_ref().unwrap().val } else { 0 };
            let count = (one_value + two_value + if step_in { 1 } else { 0 }) % 10;
            step_in = (one_value + two_value + if step_in { 1 } else { 0 }) &gt; 9;
            *cursor = Some(Box::new(ListNode { val: count, next: None }));
            cursor = &amp;mut cursor.as_mut().unwrap().next;

            if one.is_some() { one = &amp;one.as_ref().unwrap().next };
            if two.is_some() { two = &amp;two.as_ref().unwrap().next };
        }

        if step_in {
            *cursor = Some(Box::new(ListNode{ val: 1, next: None }))
        }

        head
    }
}

#[cfg(test)]
mod test {
    use crate::add_two_number::Solution;
    use crate::list::ListNode;

    #[test]
    fn should_return_708() {
        let l1 = ListNode::build_from_vec(vec![2, 4, 3]);
        let l2 = ListNode::build_from_vec(vec![5, 6, 4]);

        let ret = Solution::add_two_numbers(l1, l2);
        assert_eq!(ListNode::build_from_vec(vec![7, 0, 8]), ret);
    }
    #[test]
    fn should_return_01() {
        let l1 = ListNode::build_from_vec(vec![5]);
        let l2 = ListNode::build_from_vec(vec![5]);

        let ret = Solution::add_two_numbers(l1, l2);
        assert_eq!(ListNode::build_from_vec(vec![0, 1]), ret);
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="container-with-most-water"><a class="header" href="#container-with-most-water">container-with-most-water</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 11
/// @title Container With Most Water
/// @url https://leetcode.com/problems/container-with-most-water/
/// @difficulty medium


struct Solution;

impl Solution {
    pub fn max_area(height: Vec&lt;i32&gt;) -&gt; i32 {
        use std::cmp::{min, max};
//        let len = height.len();
//        let mut max_size = 0;
//        for start in 0..len {
//            for end in start..len {
//                let current_max = (end - start) as i32 * min(height[start], height[end]);
//                max_size = max(current_max, max_size);
//            }
//        }
//        max_size

        /// two pointer solution

        let mut start = 0usize;
        let mut end = height.len() - 1;
        let mut max_size = 0;
        while start &lt; end {
            let current_max = (end - start) as i32 * min(height[start], height[end]);
            max_size = max(current_max, max_size);
            if height[start] &lt; height[end] {
                start += 1;
            } else {
                end -= 1;
            }
        }

        max_size
    }
}


#[cfg(test)]
mod test {
    use crate::container_with_most_water::Solution;

    #[test]
    fn test() {
        assert_eq!(49, Solution::max_area(vec![1, 8, 6, 2, 5, 4, 8, 3, 7]));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="di-string-match"><a class="header" href="#di-string-match">di-string-match</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 942
/// @title DI String Match
/// @url https://leetcode.com/problems/di-string-match
/// @difficulty easy


struct Solution;

impl Solution {
    pub fn di_string_match(s: String) -&gt; Vec&lt;i32&gt; {
        let mut end = s.len() as i32;
        let mut start = 0;
        let mut ret: Vec&lt;i32&gt; = vec![];
        s.chars().for_each(|element| {
            match element {
                'I' =&gt; {
                    ret.push(start);
                    start += 1;
                }
                'D' =&gt; {
                    ret.push(end);
                    end -= 1;
                }
                _ =&gt; {}
            };
        });
        ret.push(start);
        ret
    }
}



#[test]
fn idid() {
    assert_eq!(Solution::di_string_match(String::from(&quot;IDID&quot;)), vec![0, 4, 1, 3, 2]);
}

#[test]
fn iii() {
    assert_eq!(Solution::di_string_match(String::from(&quot;III&quot;)), vec![0, 1, 2, 3]);
}

#[test]
fn ddi() {
    assert_eq!(Solution::di_string_match(String::from(&quot;DDI&quot;)), vec![3, 2, 0, 1]);
}
<span class="boring">}</span></code></pre></pre>
<h2 id="flipping-an-image"><a class="header" href="#flipping-an-image">flipping an image</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 832
/// @title Flipping an Image
/// @url https://leetcode.com/problems/flipping-an-image
/// @difficulty easy

struct Solution;

impl Solution {
    pub fn flip_and_invert_image(a: Vec&lt;Vec&lt;i32&gt;&gt;) -&gt; Vec&lt;Vec&lt;i32&gt;&gt; {
        a.into_iter()
            .map(|mut v| {
                v.reverse();
                v.into_iter()
                    .map(|element| element ^ 1)
                    .collect::&lt;Vec&lt;i32&gt;&gt;()
            })
            .collect()
    }
}


#[test]
fn test1() {
    assert_eq!(
        Solution::flip_and_invert_image(vec![vec![1, 1, 0], vec![1, 0, 1], vec![0, 0, 0]]),
        vec![vec![1, 0, 0], vec![0, 1, 0], vec![1, 1, 1]]
    )
}

#[test]
fn test2() {
    assert_eq!(
        Solution::flip_and_invert_image(vec![
            vec![1, 1, 0, 0],
            vec![1, 0, 0, 1],
            vec![0, 1, 1, 1],
            vec![1, 0, 1, 0]
        ]),
        vec![
            vec![1, 1, 0, 0],
            vec![0, 1, 1, 0],
            vec![0, 0, 0, 1],
            vec![1, 0, 1, 0]
        ]
    )
}
<span class="boring">}</span></code></pre></pre>
<h2 id="hamming-distance"><a class="header" href="#hamming-distance">hamming distance</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 461
/// @title Hamming Distance
/// @url https://leetcode.com/problems/hamming-distance
/// @difficulty easy


struct Solution;

impl Solution {
    pub fn hamming_distance(x: i32, y: i32) -&gt; i32 {
        let mut ret = x ^ y;
        let mut sum = 0;
        while ret != 0 {
            sum += ret % 2;
            ret /= 2;
        };
        sum
    }
}



#[test]
fn test() {
    assert_eq!(Solution::hamming_distance(1, 4), 2);
    assert_eq!(Solution::hamming_distance(1, 0), 1);
}
<span class="boring">}</span></code></pre></pre>
<h2 id="integer-to-roman"><a class="header" href="#integer-to-roman">integer to roman</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 12
/// @title Integer to Roman
/// @url https://leetcode.com/problems/integer-to-roman
/// @difficulty medium


struct Solution;

impl Solution {
    pub fn int_to_roman(num: i32) -&gt; String {
        let mut num_clone = num;
        let mut ret = String::new();
        while num_clone &gt; 0 {
            let x = match num_clone {
                1000...std::i32::MAX =&gt; (&quot;M&quot;, 1000),
                900...1000 =&gt; (&quot;CM&quot;, 900),
                500...900 =&gt; (&quot;D&quot;, 500),
                400...500 =&gt; (&quot;CD&quot;, 400),
                100...400 =&gt; (&quot;C&quot;, 100),
                90...100 =&gt; (&quot;XC&quot;, 90),
                50...90 =&gt; (&quot;L&quot;, 50),
                40...50 =&gt; (&quot;XL&quot;, 40),
                10...40 =&gt; (&quot;X&quot;, 10),
                9 =&gt; (&quot;IX&quot;, 9),
                5...9 =&gt; (&quot;V&quot;, 5),
                4 =&gt; (&quot;IV&quot;, 4),
                1...4 =&gt; (&quot;I&quot;, 1),
                _ =&gt; unreachable!()
            };
            ret.push_str(x.0);
            num_clone -= x.1;
        }
        ret
    }
}


#[cfg(test)]
mod test {
    use crate::integer_to_roman::Solution;

    #[test]
    fn should_return_iii_given_3() {
        assert_eq!(&quot;III&quot;, &amp;Solution::int_to_roman(3));
    }

    #[test]
    fn should_return_iv_given_4() {
        assert_eq!(&quot;IV&quot;, &amp;Solution::int_to_roman(4));
    }

    #[test]
    fn should_return_ix_given_9() {
        assert_eq!(&quot;IX&quot;, &amp;Solution::int_to_roman(9));
    }

    #[test]
    fn should_return_lviii_given_58() {
        assert_eq!(&quot;LVIII&quot;, &amp;Solution::int_to_roman(58));
    }

    #[test]
    fn should_return_mcmxciv_given_1994() {
        assert_eq!(&quot;MCMXCIV&quot;, &amp;Solution::int_to_roman(1994));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="jewels-and-stones"><a class="header" href="#jewels-and-stones">jewels and stones</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 771
/// @title Jewels and Stones
/// @url https://leetcode.com/problems/jewels-and-stones
/// @difficulty easy

struct Solution();

impl Solution {
    pub fn num_jewels_in_stones(j: String, s: String) -&gt; i32 {
        let mut sum: i32 = 0;
        j.chars().for_each(|each_char| {
            s.chars().for_each(|inner_char|{
                if inner_char == each_char {
                    sum += 1;
                }
            });
        });
        sum
    }
}



#[test]
fn all_test() {
    assert_eq!(Solution::num_jewels_in_stones(&quot;z&quot;.to_string(), &quot;ZZ&quot;.to_string()), 0);
    assert_eq!(Solution::num_jewels_in_stones(&quot;z&quot;.to_string(), &quot;zZ&quot;.to_string()), 1);
}
<span class="boring">}</span></code></pre></pre>
<h2 id="maximum-depth-of-binary-tree"><a class="header" href="#maximum-depth-of-binary-tree">maximum-depth-of-binary-tree</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 104
/// @title Maximum Depth of Binary Tree
/// @url https://leetcode.com/problems/maximum-depth-of-binary-tree
/// @difficulty easy

//Given a binary tree, find its maximum depth.
//
// The maximum depth is the number of nodes along the longest path from the root
// node down to the farthest leaf node.
//
// Note: A leaf is a node with no children.
//
// Example:
//
// Given binary tree [3,9,20,null,null,15,7],
//
//
//    3
//   / \
//  9  20
//    /  \
//   15   7
//
// return its depth = 3.
// Related Topics Tree Depth-first Search
// 👍 2511 👎 73


use std::rc::Rc;
use std::cell::RefCell;
use std::cmp::max;

struct Solution;
#[derive(Debug, PartialEq, Eq)]
pub struct TreeNode {
  pub val: i32,
  pub left: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
  pub right: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
}

impl TreeNode {
  #[inline]
  pub fn new(val: i32) -&gt; Self {
    TreeNode {
      val,
      left: None,
      right: None
    }
  }
}
//leetcode submit region begin(Prohibit modification and deletion)
// Definition for a binary tree node.

impl Solution {
    pub fn max_depth(root: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;) -&gt; i32 {
        // using reference to avoid clone
        pub fn _max_depth(root: &amp;Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;) -&gt; i32 {
            if let Some(root_node) = root {
                let node_borrow = root_node.borrow();
                let left_depth = _max_depth(&amp;node_borrow.left);
                let right_depth = _max_depth(&amp;node_borrow.right);
                std::cmp::max(left_depth, right_depth) + 1
            }else {
                0
            }
        }
        _max_depth(&amp;root)
    }
}
//leetcode submit region end(Prohibit modification and deletion)




#[cfg(test)]
mod test {
    use crate::maximum_depth_of_binary_tree::{Solution, TreeNode};
    use std::rc::Rc;
    use std::cell::RefCell;

    #[test]
    fn test() {
        let node15 = TreeNode::new(15);
        let node7 = TreeNode::new(7);

        let mut node20 = TreeNode::new(20);
        node20.left = Some(Rc::new(RefCell::new(node15)));
        node20.right = Some(Rc::new(RefCell::new(node7)));

        let node9 = TreeNode::new(9);

        let mut node3 = TreeNode::new(3);
        node3.left = Some(Rc::new(RefCell::new(node20)));
        node3.right = Some(Rc::new(RefCell::new(node9)));

        assert_eq!(3, Solution::max_depth(Some(Rc::new(RefCell::new(node3)))));
    }

    #[test]
    fn test2() {
        assert_eq!(0, Solution::max_depth(None))
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="merge-two-binary-trees"><a class="header" href="#merge-two-binary-trees">merge two binary trees</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 617
/// @title Merge Two Binary Trees
/// @url https://leetcode.com/problems/merge-two-binary-trees
/// @difficulty easy


// Definition for a binary tree node.
#[derive(Debug, PartialEq, Eq)]
pub struct TreeNode {
    pub val: i32,
    pub left: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
    pub right: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
}

impl TreeNode {
    #[inline]
    pub fn new(val: i32) -&gt; Self {
        TreeNode {
            val,
            left: None,
            right: None,
        }
    }
}

use std::cell::RefCell;
use std::rc::Rc;

struct Solution;

impl Solution {
    pub fn merge_trees(
        t1: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
        t2: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
    ) -&gt; Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt; {
        match (t1, t2) {
            (t, None) | (None, t) =&gt; t,
            (Some(t1), Some(t2)) =&gt; {
                let (t1, t2) = (t1.borrow(), t2.borrow());
                Some(Rc::new(RefCell::new(TreeNode {
                    val: t1.val + t2.val,
                    left: Solution::merge_trees(t1.left.clone(), t2.left.clone()),
                    right: Solution::merge_trees(t1.right.clone(), t2.right.clone()),
                })))
            }
        }
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="nim-game"><a class="header" href="#nim-game">nim game</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 292
/// @title Nim Game
/// @url https://leetcode.com/problems/nim-game
/// @difficulty easy

struct Solution();

impl Solution {
    pub fn can_win_nim(n: i32) -&gt; bool {
        match n {
            1...3 =&gt; true,
            _ if n % 4 == 0 =&gt; false,
            _ =&gt; true
        }
    }
}


#[test]
fn test() {
    assert!(!Solution::can_win_nim(4));
    assert!(Solution::can_win_nim(3));
    assert!(Solution::can_win_nim(6));
}
<span class="boring">}</span></code></pre></pre>
<h2 id="palindrome-number"><a class="header" href="#palindrome-number">palindrome number</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 9
/// @title Palindrome Number
/// @url https://leetcode.com/problems/palindrome-number/
/// @difficulty easy


struct Solution;


impl Solution {
    pub fn is_palindrome(x: i32) -&gt; bool {
        if x &lt; 0 { return false; }

        let string = x.to_string();
        let mut chars: Vec&lt;char&gt; = string.chars().collect();
        while chars.len() &gt; 1 {
            let last = chars.pop().unwrap();
            let first = chars.remove(0);
            if first != last {
                return false;
            }
        }
        true
    }
}

#[cfg(test)]
mod test {
    use crate::palindrome_number::Solution;

    #[test]
    fn should_return_true_given_121() {
        assert_eq!(true, Solution::is_palindrome(121));
    }
    #[test]
    fn should_return_false_given_negative_number() {
        assert_eq!(false, Solution::is_palindrome(-121));
    }
    #[test]
    fn should_return_true_given_zero() {
        assert_eq!(true, Solution::is_palindrome(0));
    }

    #[test]
    fn should_return_false_given_10() {
        assert_eq!(false, Solution::is_palindrome(10));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="permutations"><a class="header" href="#permutations">permutations</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 46
/// @title Permutations
/// @url https://leetcode.com/problems/permutations
/// @difficulty medium

//Given a collection of distinct integers, return all possible permutations.
//
// Example:
//
//
//Input: [1,2,3]
//Output:
//[
//  [1,2,3],
//  [1,3,2],
//  [2,1,3],
//  [2,3,1],
//  [3,1,2],
//  [3,2,1]
//]
//
// Related Topics Backtracking
// 👍 3843 👎 106


//leetcode submit region begin(Prohibit modification and deletion)
struct Solution;

impl Solution {
    pub fn permute(nums: Vec&lt;i32&gt;) -&gt; Vec&lt;Vec&lt;i32&gt;&gt; {
        if nums.len() &lt;= 1 { return vec![nums]; };

        let mut ret = vec![];
        for i in 0..nums.len() {
            let mut iter_ret = vec![];
            let mut cloned_nums = nums.clone();
            let index_item = cloned_nums.remove(i);
            iter_ret.push(index_item);
            for x in Solution::permute(cloned_nums) {
                let mut cloned_iter_ret = iter_ret.clone();
                cloned_iter_ret.extend(x);
                ret.push(cloned_iter_ret);
            }
        }
        ret
    }
}
//leetcode submit region end(Prohibit modification and deletion)


#[cfg(test)]
mod test {
    use crate::permutations::Solution;

    #[test]
    fn test() {
        let ret = vec![
            vec![1, 2, 3],
            vec![1, 3, 2],
            vec![2, 1, 3],
            vec![2, 3, 1],
            vec![3, 1, 2],
            vec![3, 2, 1]
        ];
        assert_eq!(ret, Solution::permute(vec![1, 2, 3]));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="reverse-integer"><a class="header" href="#reverse-integer">reverse integer</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 7
/// @title Reverse Integer
/// @url https://leetcode.com/problems/reverse-integer/
/// @difficulty easy


struct Solution;

impl Solution {
    pub fn reverse(x: i32) -&gt; i32 {
        use std::i32;
        let mut ret = 0i32;
        let mut x_clone = x;
        while x_clone != 0 {
            let i = x_clone % 10;
            let x1 = ret.overflowing_mul(10);
            if x1.1 == true {
                return 0;
            }
            let x2 = x1.0.overflowing_add(i);
            if x2.1 == true {
                return 0;
            }
            ret = x2.0;
            x_clone = x_clone / 10;
        }

        ret
    }
}


#[cfg(test)]
mod test {
    use crate::reverse_integer::Solution;

    #[test]
    fn should_return_321_given_123() {
        assert_eq!(321, Solution::reverse(123));
    }

    #[test]
    fn should_return_negative_321_given_negative_123() {
        assert_eq!(-321, Solution::reverse(-123));
    }

    #[test]
    fn should_return_21_given_120() {
        assert_eq!(21, Solution::reverse(120));
    }

    #[test]
    fn should_return_0_given_1534236469() {
        assert_eq!(0, Solution::reverse(1534236469));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="robot-return-to-origin"><a class="header" href="#robot-return-to-origin">robot return to origin</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 657
/// @title Robot Return to Origin
/// @url https://leetcode.com/problems/robot-return-to-origin
/// @difficulty easy

struct Solution;

impl Solution {
    pub fn judge_circle(moves: String) -&gt; bool {
        let mut vertical = 0;
        let mut horizon = 0;
        moves.chars().for_each(|element| {
            match element {
                'U' =&gt; { horizon += 1; }
                'D' =&gt; { horizon -= 1; }
                'L' =&gt; { vertical += 1; }
                'R' =&gt; { vertical -= 1; }
                _ =&gt; {}
            };
        });

        vertical == 0 &amp;&amp; horizon == 0
    }
}

#[test]
fn test() {
    assert!(Solution::judge_circle(String::from(&quot;UUDD&quot;)));
    assert!(!Solution::judge_circle(String::from(&quot;UUUUU&quot;)));
    assert!(Solution::judge_circle(String::from(&quot;RLUURDDDLU&quot;)));
}
<span class="boring">}</span></code></pre></pre>
<h2 id="same-tree"><a class="header" href="#same-tree">same-tree</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 100
/// @title Same Tree
/// @url https://leetcode.com/problems/same-tree
/// @difficulty easy

//Given two binary trees, write a function to check if they are the same or not.
//
//
// Two binary trees are considered the same if they are structurally identical a
//nd the nodes have the same value.
//
// Example 1:
//
//
//Input:     1         1
//          / \       / \
//         2   3     2   3
//
//        [1,2,3],   [1,2,3]
//
//Output: true
//
//
// Example 2:
//
//
//Input:     1         1
//          /           \
//         2             2
//
//        [1,2],     [1,null,2]
//
//Output: false
//
//
// Example 3:
//
//
//Input:     1         1
//          / \       / \
//         2   1     1   2
//
//        [1,2,1],   [1,1,2]
//
//Output: false
//
// Related Topics Tree Depth-first Search
// 👍 2062 👎 59


struct Solution;
#[derive(Debug, PartialEq, Eq)]
pub struct TreeNode {
  pub val: i32,
  pub left: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
  pub right: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;,
}

impl TreeNode {
  #[inline]
  pub fn new(val: i32) -&gt; Self {
    TreeNode {
      val,
      left: None,
      right: None
    }
  }
}
//leetcode submit region begin(Prohibit modification and deletion)
// Definition for a binary tree node.

use std::rc::Rc;
use std::cell::RefCell;
impl Solution {
    pub fn is_same_tree(p: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;, q: Option&lt;Rc&lt;RefCell&lt;TreeNode&gt;&gt;&gt;) -&gt; bool {
        match (p, q) {
            (Some(p_node), Some(q_node)) =&gt; {
                let (t1, t2) = (p_node.borrow(), q_node.borrow());
                let value_equals = t1.val == t2.val;

                let left_equals = Solution::is_same_tree(t1.left.clone(), t2.left.clone());
                let right_equals = Solution::is_same_tree(t1.right.clone(), t2.right.clone());
                value_equals &amp;&amp; left_equals &amp;&amp; right_equals
            },
            (None, None) =&gt; true,
            _ =&gt; false
        }
    }
}
//leetcode submit region end(Prohibit modification and deletion)




#[cfg(test)]
mod test {
    use crate::same_tree::{Solution, TreeNode};
    use std::rc::Rc;
    use std::cell::RefCell;

    #[test]
    fn test() {
        let mut node = TreeNode::new(1);
        node.left = Some(Rc::new(RefCell::new(TreeNode::new(2))));
        node.right = Some(Rc::new(RefCell::new(TreeNode::new(3))));

        let mut node2 = TreeNode::new(1);
        node2.left = Some(Rc::new(RefCell::new(TreeNode::new(2))));
        node2.right = Some(Rc::new(RefCell::new(TreeNode::new(3))));

        assert_eq!(true, Solution::is_same_tree(
            Some(Rc::new(RefCell::new(node))),
            Some(Rc::new(RefCell::new(node2))),
        ));
    }

    #[test]
    fn test2() {
        let mut node = TreeNode::new(1);
        node.left = Some(Rc::new(RefCell::new(TreeNode::new(2))));

        let mut node2 = TreeNode::new(1);
        node2.right = Some(Rc::new(RefCell::new(TreeNode::new(2))));

        assert_eq!(false, Solution::is_same_tree(
            Some(Rc::new(RefCell::new(node))),
            Some(Rc::new(RefCell::new(node2))),
        ));
    }
    #[test]
    fn test3() {
        let mut node = TreeNode::new(1);
        node.left = Some(Rc::new(RefCell::new(TreeNode::new(2))));
        node.right = Some(Rc::new(RefCell::new(TreeNode::new(1))));

        let mut node2 = TreeNode::new(1);
        node2.left = Some(Rc::new(RefCell::new(TreeNode::new(1))));
        node2.right = Some(Rc::new(RefCell::new(TreeNode::new(2))));

        assert_eq!(false, Solution::is_same_tree(
            Some(Rc::new(RefCell::new(node))),
            Some(Rc::new(RefCell::new(node2))),
        ));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="self-dividing-numbers"><a class="header" href="#self-dividing-numbers">self-dividing-numbers</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 728
/// @title Self Dividing Numbers
/// @url https://leetcode.com/problems/self-dividing-numbers
/// @difficulty easy


struct Solution;

impl Solution {
    pub fn self_dividing_numbers(left: i32, right: i32) -&gt; Vec&lt;i32&gt; {
        let mut ret = vec![];
        for index in left..=right {
            let mut index_copy = index;
            while index_copy &gt; 0 {
                let bit = index_copy % 10;
                if bit == 0 || index % bit != 0 {
                    break;
                }
                index_copy /= 10;
            };
            if index_copy == 0 {
                ret.push(index);
            }
        }
        ret
    }
}

#[test]
fn test1() {
    assert_eq!(
        Solution::self_dividing_numbers(1, 22),
        vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 22]
    );
}
<span class="boring">}</span></code></pre></pre>
<h2 id="string-to-integer"><a class="header" href="#string-to-integer">string-to-integer</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 8
/// @title String to Integer (atoi)
/// @url https://leetcode.com/problems/string-to-integer-atoi/
/// @difficulty Medium


struct Solution;

impl Solution {
    pub fn my_atoi(str_: String) -&gt; i32 {
        use std::i32;
        let mut is_getting_number = false;
        let mut is_negative: Option&lt;bool&gt; = None;
        let mut ret = 0i32;
        let x = str_.trim().chars();
        for x in x {
            match x {
                ref n if n.is_ascii_digit() =&gt; {
                    let number_in_position = n.to_digit(10).unwrap() as i32;
                    let optional_ret: Option&lt;i32&gt; = ret.checked_mul(10).and_then(|inner| inner.checked_add(number_in_position));
                    if let Some(num) = optional_ret {
                        is_getting_number = true;
                        ret = num;
                    } else {
                        if let Some(true) = is_negative {
                            return std::i32::MIN;
                        }else {
                            return std::i32::MAX;
                        }
                    }
                }
                '+' =&gt; {
                    if is_negative.is_none() &amp;&amp; is_getting_number == false {
                        is_negative = Some(false);
                    } else {
                        break;
                    }
                }
                '-' =&gt; {
                    if is_negative.is_none() &amp;&amp; is_getting_number == false {
                        is_negative = Some(true);
                    } else {
                        break;
                    }
                }
                _ =&gt; {
                    break;
                }
            }
        };
        if let Some(true) = is_negative { -ret }else { ret }

    }
}


#[cfg(test)]
mod test {
    use crate::string_to_integer_atoi::Solution;

    #[test]
    fn should_work_with_normal_number() {
        assert_eq!(42i32, Solution::my_atoi(&quot;42&quot;.into()));
    }

    #[test]
    fn should_work_with_minus_mark() {
        assert_eq!(-42i32, Solution::my_atoi(&quot;-42&quot;.into()));
    }

    #[test]
    fn should_work_with_prefix_space() {
        assert_eq!(-42i32, Solution::my_atoi(&quot;   -42&quot;.into()));
    }

    #[test]
    fn should_work_with_postfix_external_words() {
        assert_eq!(4293i32, Solution::my_atoi(&quot;4293 with words&quot;.into()));
    }

    #[test]
    fn should_get_zero_with_prefix_words() {
        assert_eq!(0i32, Solution::my_atoi(&quot;with words  4293&quot;.into()));
    }

    #[test]
    fn should_check_overflow() {
        assert_eq!(std::i32::MIN, Solution::my_atoi(&quot;-91283472332&quot;.into()));
        assert_eq!(std::i32::MAX, Solution::my_atoi(&quot;91283472332&quot;.into()));
    }

    #[test]
    fn should_work_with_add_mark() {
        assert_eq!(42i32, Solution::my_atoi(&quot;+42&quot;.into()));
    }

    #[test]
    fn should_work_with_both_add_minus_mark() {
        assert_eq!(0i32, Solution::my_atoi(&quot;+-42&quot;.into()));
    }

    #[test]
    fn should_get_zero_with_internal_space() {
        assert_eq!(4i32, Solution::my_atoi(&quot;+4 2&quot;.into()));
    }

    #[test]
    fn test() {
        assert_eq!(4i32, Solution::my_atoi(&quot;+4 2&quot;.into()));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="sudoku-solver"><a class="header" href="#sudoku-solver">sudoku-solver</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 37
/// @title Sudoku Solver
/// @url https://leetcode.com/problems/sudoku-solver/
/// @difficulty Hard

struct Solution;

impl Solution {
    pub fn solve_sudoku(board: &amp;mut Vec&lt;Vec&lt;char&gt;&gt;) {
        let mut empty_position = vec![];
        for i in 0..9 {
            for j in 0..9 {
                if board[i][j] == '.' {
                    empty_position.push((i, j));
                    board[i][j] = '0';
                }
            }
        }
        let position_len = empty_position.len();

        let mut loop_index = 0;
        while loop_index &lt; position_len {
            let (x, y) = empty_position[loop_index];

            if board[x][y] &lt; '9' {
                board[x][y] = std::char::from_u32((board[x][y] as u32) + 1).unwrap();
            } else {
                board[x][y] = '0';
                loop_index -= 1;
                continue;
            }
            if Solution::invalid(board, x, y) {
                continue;
            }
            loop_index += 1;
        }
    }
    pub fn invalid(board: &amp;Vec&lt;Vec&lt;char&gt;&gt;, x: usize, y: usize) -&gt; bool {
        use std::collections::HashSet;
        let mut contain_table = HashSet::new();

        // validate line
        for i in 0..9 {
            let x1 = board[x][i];
            if x1 != '0' {
                if contain_table.contains(&amp;x1) {
                    return true;
                }
                contain_table.insert(x1);
            }
        }
        contain_table.clear();

        // validate column

        for i in 0..9 {
            let x2 = board[i][y];
            if x2 != '0' {
                if contain_table.contains(&amp;x2) {
                    return true;
                }
                contain_table.insert(x2);
            }
        }

        contain_table.clear();
        // validate box

        let i1 = x / 3;
        let i2 = y / 3;
        for i in 0..3 {
            for j in 0..3 {
                let x3 = board[i1 * 3 + i][i2 * 3 + j];
                if x3 != '0' {
                    if contain_table.contains(&amp;x3) {
                        return true;
                    }
                    contain_table.insert(x3);
                }
            }
        }
        contain_table.clear();
        false
    }
}

#[cfg(test)]
mod test {
    use crate::sudoku_solver::Solution;

    #[test]
    fn test() {
        let mut sudoku = vec![
            vec!['5', '3', '.', '.', '7', '.', '.', '.', '.'],
            vec!['6', '.', '.', '1', '9', '5', '.', '.', '.'],
            vec!['.', '9', '8', '.', '.', '.', '.', '6', '.'],
            vec!['8', '.', '.', '.', '6', '.', '.', '.', '3'],
            vec!['4', '.', '.', '8', '.', '3', '.', '.', '1'],
            vec!['7', '.', '.', '.', '2', '.', '.', '.', '6'],
            vec!['.', '6', '.', '.', '.', '.', '2', '8', '.'],
            vec!['.', '.', '.', '4', '1', '9', '.', '.', '5'],
            vec!['.', '.', '.', '.', '8', '.', '.', '7', '9'],
        ];
        Solution::solve_sudoku(&amp;mut sudoku);

        let mut expected_solution = vec![
            vec!['5', '3', '4', '6', '7', '8', '9', '1', '2'],
            vec!['6', '7', '2', '1', '9', '5', '3', '4', '8'],
            vec!['1', '9', '8', '3', '4', '2', '5', '6', '7'],
            vec!['8', '5', '9', '7', '6', '1', '4', '2', '3'],
            vec!['4', '2', '6', '8', '5', '3', '7', '9', '1'],
            vec!['7', '1', '3', '9', '2', '4', '8', '5', '6'],
            vec!['9', '6', '1', '5', '3', '7', '2', '8', '4'],
            vec!['2', '8', '7', '4', '1', '9', '6', '3', '5'],
            vec!['3', '4', '5', '2', '8', '6', '1', '7', '9'],
        ];
        assert_eq!(expected_solution, sudoku);
    }

    #[test]
    fn test_invalid_method() {
        let mut expected_solution = vec![
            vec!['5', '3', '4', '6', '7', '8', '9', '1', '2'],
            vec!['6', '7', '2', '1', '9', '5', '3', '4', '8'],
            vec!['1', '9', '8', '3', '4', '2', '5', '6', '7'],
            vec!['8', '5', '9', '7', '6', '1', '4', '2', '3'],
            vec!['4', '2', '6', '8', '5', '3', '7', '9', '1'],
            vec!['7', '1', '3', '9', '2', '4', '8', '5', '6'],
            vec!['9', '6', '1', '5', '3', '7', '2', '8', '4'],
            vec!['2', '8', '7', '4', '1', '9', '6', '3', '5'],
            vec!['3', '4', '5', '2', '8', '6', '1', '7', '9'],
        ];
        for i in 0..9 {
            for j in 0..9 {
                assert_eq!(false, Solution::invalid(&amp;expected_solution, i, j));
            }
        }
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="to-lower-case"><a class="header" href="#to-lower-case">to-lower-case</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 709
/// @title To Lower Case
/// @url https://leetcode.com/problems/to-lower-case
/// @difficulty easy


struct Solution();

impl Solution {
    pub fn to_lower_case(str: String) -&gt; String {
        str.as_str().to_lowercase()
    }
}


#[test]
fn test() {
    assert_eq!(Solution::to_lower_case(String::from(&quot;HELLO&quot;)), String::from(&quot;hello&quot;));
}
<span class="boring">}</span></code></pre></pre>
<h2 id="two-sum"><a class="header" href="#two-sum">two sum</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 1
/// @title Two Sum
/// @url https://leetcode.com/problems/two-sum
/// @difficulty easy


struct Solution;

impl Solution {
    pub fn two_sum(nums: Vec&lt;i32&gt;, target: i32) -&gt; Vec&lt;i32&gt; {
        use std::collections::HashMap;
        let mut r: HashMap&lt;i32, i32&gt; = HashMap::new();
        for i in 0..nums.len() {
            r.insert(nums[i], i as i32);
        }
        for i in 0..nums.len() {
            match r.get(&amp;(target - nums[i])) {
                Some(index) if i as i32 != *index =&gt; return vec![i as i32, index.clone()],
                None =&gt; {}
                _ =&gt; {}
            }
        }
        vec![]
    }
}

#[test]
fn test1() {
    assert_eq!(Solution::two_sum(vec![2, 7, 11, 15], 9), vec![0, 1]);
}

#[test]
fn test2() {
    assert_eq!(Solution::two_sum(vec![2, 7, 11, 15], 9999), vec![]);
}

#[test]
fn test3() {
    assert_eq!(Solution::two_sum(vec![3, 2, 4], 6), vec![1, 2]);
}
<span class="boring">}</span></code></pre></pre>
<h2 id="unique-email-addresses"><a class="header" href="#unique-email-addresses">unique-email-addresses</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 929
/// @title Unique Email Addresses
/// @url https://leetcode.com/problems/unique-email-addresses
/// @difficulty easy


struct Solution();

impl Solution {
    pub fn num_unique_emails(emails: Vec&lt;String&gt;) -&gt; i32 {
        let mut real_emails = emails.into_iter().map(|email| {
            let email_split: Vec&lt;&amp;str&gt; = email.split('@').collect();
            let name_slit: Vec&lt;&amp;str&gt; = email_split[0].split('+').collect();
            let real_name = name_slit[0].replace(&quot;.&quot;, &quot;&quot;);
            format!(&quot;{}@{}&quot;, real_name, email_split[1])
        }).collect::&lt;Vec&lt;String&gt;&gt;();
        println!(&quot;{:?}&quot;, real_emails);
        real_emails.sort();
        // dedup can only be used for sorted data.
        real_emails.dedup_by(|a, b| a == b);

        real_emails.len() as i32
    }
}


#[test]
fn test() {
    assert_eq!(Solution::num_unique_emails(vec![&quot;a@a.com&quot;.to_string(), &quot;a+a@a.com&quot;.to_string()]), 1);

    assert_eq!(Solution::num_unique_emails(vec![
        &quot;fg.r.u.uzj+o.pw@kziczvh.com&quot;.to_string(),
        &quot;r.cyo.g+d.h+b.ja@tgsg.z.com&quot;.to_string(),
        &quot;fg.r.u.uzj+o.f.d@kziczvh.com&quot;.to_string(),
        &quot;r.cyo.g+ng.r.iq@tgsg.z.com&quot;.to_string(),
        &quot;fg.r.u.uzj+lp.k@kziczvh.com&quot;.to_string(),
        &quot;r.cyo.g+n.h.e+n.g@tgsg.z.com&quot;.to_string(),
        &quot;fg.r.u.uzj+k+p.j@kziczvh.com&quot;.to_string(),
        &quot;fg.r.u.uzj+w.y+b@kziczvh.com&quot;.to_string(),
        &quot;r.cyo.g+x+d.c+f.t@tgsg.z.com&quot;.to_string(),
        &quot;r.cyo.g+x+t.y.l.i@tgsg.z.com&quot;.to_string(),
        &quot;r.cyo.g+brxxi@tgsg.z.com&quot;.to_string(),
        &quot;r.cyo.g+z+dr.k.u@tgsg.z.com&quot;.to_string(),
        &quot;r.cyo.g+d+l.c.n+g@tgsg.z.com&quot;.to_string(),
        &quot;fg.r.u.uzj+vq.o@kziczvh.com&quot;.to_string(),
        &quot;fg.r.u.uzj+uzq@kziczvh.com&quot;.to_string(),
        &quot;fg.r.u.uzj+mvz@kziczvh.com&quot;.to_string(),
        &quot;fg.r.u.uzj+taj@kziczvh.com&quot;.to_string(),
        &quot;fg.r.u.uzj+fek@kziczvh.com&quot;.to_string()
    ]), 2);
}
<span class="boring">}</span></code></pre></pre>
<h2 id="unique-morse-code-words"><a class="header" href="#unique-morse-code-words">unique morse code words</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 804
/// @title Unique Morse Code Words
/// @url https://leetcode.com/problems/unique-morse-code-words
/// @difficulty easy


struct Solution();

impl Solution {
    pub fn unique_morse_representations(words: Vec&lt;String&gt;) -&gt; i32 {
        let morse = [
            &quot;.-&quot;, &quot;-...&quot;, &quot;-.-.&quot;, &quot;-..&quot;, &quot;.&quot;, &quot;..-.&quot;, &quot;--.&quot;, &quot;....&quot;, &quot;..&quot;, &quot;.---&quot;, &quot;-.-&quot;, &quot;.-..&quot;,
            &quot;--&quot;, &quot;-.&quot;, &quot;---&quot;, &quot;.--.&quot;, &quot;--.-&quot;, &quot;.-.&quot;, &quot;...&quot;, &quot;-&quot;, &quot;..-&quot;, &quot;...-&quot;, &quot;.--&quot;, &quot;-..-&quot;,
            &quot;-.--&quot;, &quot;--..&quot;,
        ];

        let mut words_morse = words
            .into_iter()
            .map(|word| {
                word.chars()
                    .map(|each_char| {
                        let index = each_char as usize - 97;
                        morse[index].to_string()
                    })
                    .collect::&lt;Vec&lt;String&gt;&gt;()
                    .join(&quot;&quot;)
            })
            .collect::&lt;Vec&lt;String&gt;&gt;();

        words_morse.sort();
        words_morse.dedup_by(|a, b| a == b);

        words_morse.len() as i32
    }
}


#[test]
fn test1() {
    assert_eq!(
        Solution::unique_morse_representations(vec![
            String::from(&quot;gin&quot;),
            String::from(&quot;zen&quot;),
            String::from(&quot;gig&quot;),
            String::from(&quot;msg&quot;),
        ]),
        2
    );
}
<span class="boring">}</span></code></pre></pre>
<h2 id="unique-vec"><a class="header" href="#unique-vec">Unique Vec</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>use std::collections::BTreeSet;
fn unique_in_order(vec: Vec&lt;i32&gt;) -&gt; Vec&lt;i32&gt; {
            let mut bset = BTreeSet::new();
            for i in vec {
                bset.insert(i);
            }
            let mut re_vec = Vec::new();
            for item in &amp;bset {
                re_vec.push(*item);
            }
            re_vec
}

fn unique_in_order&lt;T&gt;(sequence: T) -&gt; Vec&lt;T::Item&gt;
    where
        T: std::iter::IntoIterator,
        T::Item: std::cmp::PartialEq + std::fmt::Debug,
    {
        let mut v: Vec&lt;_&gt; = sequence.into_iter().collect();
        v.dedup();
        v
    }
<span class="boring">}</span></code></pre></pre>
<h2 id="zigzag-conversion"><a class="header" href="#zigzag-conversion">zigzag conversion</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/// @number 6
/// @title ZigZag Conversion
/// @url https://leetcode.com/problems/zigzag-conversion
/// @difficulty medium

struct Solution;


impl Solution {

    pub fn convert(s: String, num_rows: i32) -&gt; String {
        if num_rows == 1 {
            return s;
        }
        let chars: Vec&lt;char&gt; = s.chars().collect();

        let mut strings: Vec&lt;String&gt; = (0..num_rows).map(|_| String::new()).collect();
        let mut go_down = false;
        let mut loop_line = 0 as i32;

        for x in chars {
            strings[loop_line as usize].push(x);
            if loop_line == 0  || loop_line == num_rows - 1 {
                go_down = !go_down;
            }
            loop_line += if go_down { 1 } else { -1 };
        }
        strings.join(&quot;&quot;)
    }

}

#[cfg(test)]
mod test {
    use crate::zigzag_conversion::Solution;

    #[test]
    fn show_return_itself_when_number_is_1() {
        assert_eq!(String::from(&quot;PAYPALISHIRING&quot;), Solution::convert(String::from(&quot;PAYPALISHIRING&quot;), 1));

    }
    #[test]
    fn should_it_works() {
        assert_eq!(String::from(&quot;PAHNAPLSIIGYIR&quot;), Solution::convert(String::from(&quot;PAYPALISHIRING&quot;), 3));
    }
    #[test]
    fn should_it_works_too() {
        assert_eq!(String::from(&quot;PINALSIGYAHRPI&quot;), Solution::convert(String::from(&quot;PAYPALISHIRING&quot;), 4));
    }
}
<span class="boring">}</span></code></pre></pre>
<h2 id="丑数-ii"><a class="header" href="#丑数-ii"><a href="https://leetcode.cn/problems/ugly-number-ii/">丑数 II</a></a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>/*
https://leetcode.cn/problems/ugly-number-ii/
*/
impl Solution {
 pub fn nth_ugly_number(n: i32) -&gt; i32 {
    let mut ugly = vec![1; n as usize];
    let mut idx = vec![0; 3 as usize];
    for i in 1..n {
        let a = ugly[idx[0]] * 2;
        let b = ugly[idx[1]] * 3;
        let c = ugly[idx[2]] * 5;
        let next = std::cmp::min(a, std::cmp::min(b, c));
        if next == a {
            idx[0] += 1;
        }
        if next == b {
            idx[1] += 1;
        }
        if next == c {
            idx[2] += 1;
        }
        ugly[i as usize] = next;
    }
    ugly.pop().unwrap()
}
}
<span class="boring">}</span></code></pre></pre>
<h2 id="不用临时变量替换number"><a class="header" href="#不用临时变量替换number">不用临时变量替换Number</a></h2>
<pre><code>use std::ops::{Add, Sub};
use doe::traits::Print;
fn main() {
    let mut a = 10;
    let mut b = 90;
    swap(&amp;mut a, &amp;mut b);
    a.println();
    b.println();
}
///do't use temp varible to swap two number
fn swap&lt;T&gt;(a: &amp;mut T, b: &amp;mut T)
where
    T: Add&lt;Output = T&gt; + Sub&lt;Output = T&gt;+Copy,
{
    *a = *a + *b;
    *b = *a - *b;
    *a = *a - *b;
}
</code></pre>

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